The background of the invention will be discussed in two parts:
1. Field of the Invention
This invention relates to toys, and more particularly to a toy device utilizing an impregnated paper and a chemically reactive marker for drawing thereon.
2. Description of the Prior Art
Toys or games utilizing a writing surface in conjunction with a marker wherein one or both items have suitable color activating means are shown and described in U.S. Pat. Nos. 3,454,344 and 3,826,499. In the first of the two referenced patents a writing surface colored by a pH sensitive dye has invisible markings applied thereto by a suitable writing instrument which is not pH sensitive, the writing instrument preferably having the same color as the surface. The marking of the writing instrument provides a shield to the so-marked surface, whereby upon application of a solution of a given pH, the color of the writing surface changes in the unshielded areas due to a shift in the pH range due to the chemical reaction of the solution in the writing instrument with the solution of the surface.
U.S. Pat. No. 3,826,499 illustrates a game device which includes defined areas having different invisible ink markings whereby the marking of one of said areas by a player with a color changing chemical marking means provides a differing game-scoring response from the marking of the other area. Marking sheets are used which can be treated with a suitable acid or base material which remains substantially invisible with the writing instrument being provided with appropriate color changing chemical materials.
Both devices simply employ a sheet of paper suitably treated in conjunction with a chemically reactive solution which may be handled or carried in a felt tip marker pen or in a sponge or the like. In one device, a wax crayon is utilized to shield certain portions of the treated paper so that upon application of the chemically reactive solution to the paper the wax coated portions protect the paper solution.
Such devices are generally not suitable for children of tender years. Pre-school children and children in the early grades are, however, fond of coloring books and the like. Furthermore, such children are fascinated with unusual effects.
Accordingly, it is an object of this invention to provide a new and improved device utilizing chemically reactive writing surfaces and markers.
It is another object of this invention to utilize an impregnated paper having an opaque quality in conjunction with a lighted surface.
It is a further object of this invention to provide a new and improved toy having an illuminated surface for retaining an opaque treated paper for use in conjunction with markers having chemically reactive solutions rendering the opaque paper translucent in differing colors upon marking.